The 30-30-30 training routine is one that I heard about a few years ago, and I usually invoke it once a year when I feel like I need to get back into regular, consistent training in a particular discipline. The basic idea is:
30 sessions of 30 minutes each in 30 days
Sort of force yourself to do some really, really consistent and regular training for a while, perhaps more so than you normally would
30 minutes should be short enough, and not have too much impact on your body, that you can aim to do it (on average) every day
30 days should be long enough duration for you to re-establish some good habits in your training
You can double up one day if you know you won't be able to do your training the next day (e.g. one 30-minute run in the morning, another 30-minute run in the evening)
A longer run of 90 minutes or more can count as 2 runs, as well
In my experience, it is a great way to "jump start" your training after some down time. It is also a great way to examine your daily and weekly routines, trying to find a little more flexibility than you might have thought you had. It can be a great way to reinforce the notion of "little and often" that I find can be a great mantra to repeat, from time to time.